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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Use ST_DWithin (works for both geography and geometry) and any kind of geometry, not just lines . <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>My example is for geography since units are always in meters. For geometry units you have to specify based on your spatial_ref_sys and geometries have to have same spatial ref sys<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>something like below will return all roads that are within 100 meters of a fault line<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>SELECT l.gid, l.geog<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>FROM roads As l<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>WHERE EXISTS (SELECT 1 FROM fault_lines As fl WHERE ST_DWithin(fl.geog, l.geog, 100) );<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>If you need to know the exact fault lines, do a JOIN instead – keep in mind if a road is close enough to more than one fault line, it will be duplicated<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>SELECT l.gid, l.geog, fl.name, ST_Distance(l.geog, fl.geog) AS dist<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>FROM roads AS l INNER JOIN fault_lines AS fl ON (ST_DWithin(fl.geog, l.geog, 100) );<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>If you want jus the closes fault line within 100 meters use DISTINCT ON<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>SELECT DISTINCT ON(l.gid) l.gid, l.geog, fl.name, ST_Distance(l.geog, fl.geog) AS dist<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>FROM roads AS l INNER JOIN fault_lines AS fl ON (ST_DWithin(fl.geog, l.geog, 100) )<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>ORDER BY l.gid, dist;<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Hope that helps,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Regina<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><a href="http://www.postgis.us">http://www.postgis.us</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><a href="http://www.paragoncorporation.com">http://www.paragoncorporation.com</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><a href="http://postgis.net">http://postgis.net</a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> postgis-users [mailto:postgis-users-bounces@lists.osgeo.org] <b>On Behalf Of </b>Ahmet Temiz<br><b>Sent:</b> Sunday, October 30, 2016 2:59 AM<br><b>To:</b> PostGIS Users Discussion <postgis-users@lists.osgeo.org>; PostGIS Users Discussion <postgis-users@postgis.refractions.net><br><b>Subject:</b> [postgis-users] Line within range of another line?<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'>Hi,<o:p></o:p></p><div><p class=MsoNormal style='margin-left:.5in'>How can I find Line within range of another line?<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>I mean I try to find line section within certain range of another line.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>For example, road lines close to fault lines.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>Ps : I know that using st_buffer causes performance issue.<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>Can you give any advice?<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>Regards<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><p class=MsoNormal style='margin-left:.5in'><br><br>-- <o:p></o:p></p><div><div><div><div><p class=MsoNormal style='margin-left:.5in'>Ahmet Temiz<br>Jeoloji Müh.<br>Afet ve Acil Durum Yönetimi Başkanlığı<br>Bilgi İşlem Dairesi Başkanlığı-CBS Grubu<br><br><br>________________________<br><br>Ahmet Temiz<br>Geological Eng.<br>Information Systems - GIS Group<br>Disaster and Emergency Management<br>of Presidency<o:p></o:p></p></div></div></div></div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div></body></html>